In Rockville, Md., you will be slapped with a misdemeanor if caught swearing while on a highway. Luckily, you'll only be fined if your profane language is uttered "within the hearing of persons passing by." If a driver curses in Rockville and no one is there to hear him, does he make a sound?

In University City, Mo., you cannot honk the horn of someone else's car. Tooting your own horn, however, is entirely legal.

In New Jersey, drivers are required to beep their car horns before passing another vehicle. Technically, the law requires "audible warning" with a "warning device," so feel free to ditch your horn and get creative.

In Blairstown, N.J., it is illegal to plant trees in the middle of the street. Luckily most people find it very difficult to do in the first place.

In Sag Harbor, N.Y., it is illegal to disrobe in your car.

In West Virginia, it is perfectly legal, for road maintenance purposes, to scavenge road kill. What's for dinner?

In Hilton Head, S.C., you cannot leave trash in your vehicle out of fear of attracting rats.